BigTerp's Tracker Sportsman 16' O/B Jet build

TinBoats.net

Help Support TinBoats.net:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.
Taking her out this evening after work to test run the new motor setup. My buddy got the control wires ran through the rear bench seat, hooked up and adjusted over the weekend. She should be ready to go. Can hardly wait. Wish me luck!!!! [-o<
 
[url=https://www.tinboats.net/forum/viewtopic.php?p=330806#p330806 said:
BigTerp » 33 minutes ago[/url]"]Taking her out this evening after work to test run the new motor setup. My buddy got the control wires ran through the rear bench seat, hooked up and adjusted over the weekend. She should be ready to go. Can hardly wait. Wish me luck!!!! [-o<
i need a buddy like that! does he put gas in the boat too?
 
[url=https://www.tinboats.net/forum/viewtopic.php?p=330810#p330810 said:
typed by ben » Today, 8:58 am[/url]"]
[url=https://www.tinboats.net/forum/viewtopic.php?p=330806#p330806 said:
BigTerp » 33 minutes ago[/url]"]Taking her out this evening after work to test run the new motor setup. My buddy got the control wires ran through the rear bench seat, hooked up and adjusted over the weekend. She should be ready to go. Can hardly wait. Wish me luck!!!! [-o<
i need a buddy like that! does he put gas in the boat too?

HA, not yet. Not sure if you read through this thread or not, but he actually bought the motor off Craigslist blown up and in need of a rebuild and I helped him rebuild it. Actually, I just basically handed him tools and beer. Can't beat that!! He's a hell of a guy. He's my hunting partner 99% of the time and fishing partner 75% of the time. And after all his help with this project, not to mention the motor, he's free to use my boat anytime he wants.
 
[url=https://www.tinboats.net/forum/viewtopic.php?p=330899#p330899 said:
Ranchero50 » Yesterday, 9:05 pm[/url]"]So was it everything you expected it to be?

Not even close!! But we are hoping we have the problem figured out. The engine seems to be running in S.L.O.W. mode. Which is a fail safe that if the engine overheats or the oil injection system isn't functioning it limits the rpms to 2500, even at WOT. We don't have a tach or anyway to tell what the rpms are, but it sure seems like that is the case. We aren't using the oil injection system, so it may be as simple as disconnecting that wire from the engine. If that doesn't work, we'll have to take a look at the temp switches to see if they are bad. Hoping one or both of those are the problem, if not we'll move on down the line until we figure it out. Won't get to trouble shoot unitl tomorrow evening and will take her back out Thursday.

Other than that everything went well. My controls and stick steer functioned great, motor started right up each time, transom riser seems solid, timing is on the money, plugs looked good and even though we didn't get up on plane the jet foot seems to be set almost perfect. That may change once we get on plane, but I'm hoping not.

Will do some trouble shooting tomorrow evening. Hopefully it will be a quick and obvious fix!!! [-o<
 
[url=https://www.tinboats.net/forum/viewtopic.php?p=330836#p330836 said:
BigTerp » Yesterday, 11:55[/url]"]

HA, not yet. Not sure if you read through this thread or not, but he actually bought the motor off Craigslist blown up and in need of a rebuild and I helped him rebuild it. Actually, I just basically handed him tools and beer. Can't beat that!! He's a hell of a guy. He's my hunting partner 99% of the time and fishing partner 75% of the time. And after all his help with this project, not to mention the motor, he's free to use my boat anytime he wants.
yeah thats a good deal there.
 
That sucks... I have a buddy at work who's dealing with the same thing. His VRO oil level sensor is unplugged, no difference and is expecting to buy a power pack. His was a used motor off eBay so who knows the history.
 
[url=https://www.tinboats.net/forum/viewtopic.php?p=330933#p330933 said:
Ranchero50 » 4 minutes ago[/url]"]That sucks... I have a buddy at work who's dealing with the same thing. His VRO oil level sensor is unplugged, no difference and is expecting to buy a power pack. His was a used motor off eBay so who knows the history.

Yeah, power pack could also be the problem, hoping not. We are going to use an ohmeter and start trouble shooting. Could me a multitude of things. Blocking diode could also be bad allowing something else to engage S.L.O.W. mode that shouldn't.

Should I be getting a horn/alarm if it's in S.L.O.W. mode? We don't. I'm also thinking that when I turn the key on I should get a horn/alarm kind of as an everything is ok sort of thing. I haven't heard anything from the engine. Maybe the horn/alarm is bad as well?
 
Did a little tyding up last night and grabbed a few pictures of the motor setup. The transom riser is 2 pieces of aluminum sheet that sandwiches the transom. There is another piece of sheet welded to the back side of the fore sheet that acts as a spacer for the transom. Where the top of the transom meets my transom wood, there is a small space, hence the need for a spacer. The top part of the transom riser accounts for 4-5/8" of rise which allows the front of the jet foot to sit flush with the bottom of my hull. The transom riser is made up of various pieces of aluminum sheet that makes one large piece that is all welded together. The motor is bolted through the riser and transom with four 1/2" stainless bolts and nyloc nuts. If any adjustment is needed (probably down if anything) we can knock off small amounts of the top part of the riser as needed. The four bolts I have in now will allow for adjustment without having to drill anymore holes through my transom. Once everything is dialed in, I'll be adding 2 more bolts through my transom to finalize the motor install.

IMAG1001_zpsdd68622b.jpg


IMAG1003_zps93ce3295.jpg


IMAG1002_zps1e95ee67.jpg


A few pictures of my controls and stick steer.
IMAG1004_zps66eb2a2a.jpg


IMAG1005_zps5f162cd1.jpg


Hoping to get my hands on an ohmeter tonight so we can start diagnosising the motor. Hopefully it'll be something fairly simple that is causing our problems.
 
try disconnecting the temp sending units from the harness as a quick and free test and see if the motor opens up. the oil injection wires must also be unplugged from the oil tank. heres a video of my motor going into slow mode to help you determine if its slow mode.

https://www.youtube.com/watch?v=8c28Znn-6Wc&feature=youtu.be

ive got plenty of tools if you need them.
 
[url=https://www.tinboats.net/forum/viewtopic.php?p=331118#p331118 said:
JoshKeller » Yesterday, 10:29 pm[/url]"]try disconnecting the temp sending units from the harness as a quick and free test and see if the motor opens up. the oil injection wires must also be unplugged from the oil tank. heres a video of my motor going into slow mode to help you determine if its slow mode.

https://www.youtube.com/watch?v=8c28Znn-6Wc&feature=youtu.be

ive got plenty of tools if you need them.

Thanks man!! I'm hoping the motor is going into SLOW mode. Can't really figure out what else is going on, unless the power pack is bad. My buddy is stopping by this evening with a megaohmeter so we can test all the possibilities. The weird thing is the motor never gets wide open. It starts fine, but when you go full throttle it seems bogged down and like it doesn't want to open up all the way. I notice how yours seems to act fine and then you can see when it goes into SLOW mode. Mine seems to be constantly in slow mode. Other odd thing is there is no horn/alarm sounding. The alarm could be bad, or the blocking diode could also be bad causing something else to engage SLOW mode that won't set off an alarm. Either way after tonight, we should have a good idea of what is wrong. Wish me luck!!! [-o<
 
So my buddy brought his ohmeter over tonight and everything seems to check out. Power pack, temp switches, etc. are all good. We were able to ground the temp switch and run the motor in a barrel to put it in SLOW mode. SLOW mode isn't our problem. SLOW mode is very noticeable and different then what the motor is doing. While running in the barrel the motor would run at WOT but bogged down. Then when the water level in the barrel would start dropping the motor would open up and run like it should. It's almost as if the water going into the pump is causing some sort of restriction. Now, I checked my impeller clearance last night. It's not uniform. Some spots are tighter than .020 and others are over.027. If I rotate the flywheel, the clearances stay at the same spot in respect to the liner. So it doesn't seem to be a bent shaft, but more like an imperfect liner. But the liner isn't gouged or marked at all. Not sure if that could be causing this issue or not. My buddys guess it's there is some sort of restriction within the exhaust. Basically when there is any load on the motor it doesn't want to open up. Anyone have any ideas?
 
have you verified all the carbs are opening up properly? does the timing advance arm move freely? it almost sounds like the lower water level is reducing the exhaust pressure, sort of like running it on muffs instead of submerged.
 
[url=https://www.tinboats.net/forum/viewtopic.php?p=331211#p331211 said:
JoshKeller » Yesterday, 9:13 pm[/url]"]have you verified all the carbs are opening up properly? does the timing advance arm move freely? it almost sounds like the lower water level is reducing the exhaust pressure, sort of like running it on muffs instead of submerged.

Thanks for the thoughts!!! I forwarded this to my buddy to see what he thinks. I haven't checked to see if the carbs are opening up properly or if the timing advance arm is moving freely, but he may have. He's the engine guy not me :p . Actually it's the opposite of what your saying. When the pump is completely submerged the engine won't open up. Once the water in the barrell starts to lower, the engine then seems to run like it should and opens up. It acts as if the water pressure within the pump is restricting something, or if any load is on the engine it won't open up. Kind of like what you'd experience when getting cavitation. But my engine never fully revs until the pump starts to come out of the water. Make sense?
 
Thanks Jaime!!

My buddy confirmed the carbs are opening up fine and the timing arm is good to go. We also inspected the reed valves when we had the powerhead apart and they looked fine. This is why it's driving him bonkers trying to figure this thing out!! The motor is marked from OMC with a model number that translates into 50hp jet. So I'm almost positive OMC built the motor with the jet pump installed. I checked outboard jets website and got the jet pump model # that should be on this motor. I'll double check tonight to see if I can find a model number on the pump just to be sure.

My buddy is thinking there is a crack or hole in the exhaust tube. We are going to inspect it in the morning. He also wants to back the boat in the river to be able to run it with just the foot submerged. I'm guessing this would confirm if it's some sort of exhaust issue?
 
I'm still going to say reeds. If they are to strong they won't let enough air into the bottom end and if too weak they won't seat quick enough for the piston stroke to push the fuel charge into the cylinder. You can check that by running it with the top and carb hat off. If you can feel air puffing or pulsing out the carb inlet you may have problems. Get a set of Beyensons to put in.

Also, did you guys do a WOT chop? Run the engine at max throttle for a minute and pull the kill switch. Drop anchor and pop the plugs out to inspect how the engine is firing at WOT.

Per exhaust, there's really nothing there to get blocked. You should be able to pull a spark plug and force compressed air into the cylinder to check for exhaust flow.

Good luck.
 
Thanks Jamie. I think you might be right on the reeds. It's the only thing that makes sense. I checked compression tonight. Was a hair over145 bottom cylinder and almost 150 on the top. So that checked out. My buddy checked the spark yesterday and all was good. Going to go over ALL the electrical components tomorrow just to rule everything else out. Will probably be ordering reeds tomorrow as well. Thanks for the help!!!
 

Latest posts

Top